I think most of the obvious things have already been said OP. I'm messy like your wife. I don't think DH believes me but I honestly can't help it. I run around like a blue arsed fly all day and still don't get nearly enough done around the house (I work FT as well). We argue about it every few months. I was brought up in a messy house so our house never looks that bad to me.
Things that help us:
Declutter. DH is very good at leading on this. The one rule is that he is not allowed to touch or pass comment on the inside of my wardrobe (as long as the doors still shut!).
For stuff your wife is having trouble letting go of, you could try a phased declutter. Box up things you don't use often and put them somewhere else (garage, loft etc). If you don't end up going and retrieving them after 6-12 months, then get rid. But be careful you don't just end up buying replacements!
Dishwasher: DH fills it, I empty it. Somehow that keeps the momentum going.
Agree with pp saying divide the household jobs according to your strengths. Don't expect her to do jobs that require a high attention to detail.
It's hard when there's a buildup of resentment but try and make yourself comment positively when she does get some tidying/cleaning done, even if it's not perfect. DH sometimes doesn't seem to notice the stuff I do manage to get done, even if it took me ages, and it's really demotivating.
Oh, and don't separate laundry by whose it is. That is a bit petty and just makes more work. Have 1 big laundry basket for the family and separate by colour.